Any thoughts on this?

For as long as I could remember my mother has always been depressed. Everyone in my family always knew there was something wrong with her but it never got bad then it has. And when I mean depressed I mean depressed. I never grew up with a father figure. I have had 2 step dads that never stayed. And my biological father is physically abusive which I have experienced. Growing up i lived with my mother and brother. Me and my brother are 9 years apart. With my mother being depressed to the point she couldn’t take care of me, my brother did. Without my brother I would be dead, sad to say Ik. I always pictured my brother as my knight and shinning armor, my super hero. There was times my 5 year old self had to look at my depressed mother in bed and I could see her bones and I had to beg her to eat. My mom was always skinny, but it was much different when she was depressed, you could see her skeleton and skull. It was pretty scary to witness at a young age. There was weeks me and my brother went without food, water, heat and electricity. My grandparents did whatever they could to help us. Mh grandparents did understand somewhat of the situation. My grandmother has a scar from my mother when she was younger and my grandfather had knee problems for which my mother had done in the past. But they didn’t fully understand how she had gotten worse when I was born. My mother had never been happy, so everytime someone in my family tells me a happy memory of her i can’t really picture it in my mind. When my brother turned 21 he moved out, and only my mother got worst. My brother admitted to me when I was 13 that my mother has gotten worst since I was born. My family always told me it wasn’t my fault but I always held that guilt on my back. She was still depressed when he left but that came along with a lot of anger. She was verbally, mentally and emotionally abusive as she still is. Instead of my own mother being the parent I felt like I always was. I went food shopping, I did the laundry, I took out the trash, I cooked meals, I helped pay bills. I did everything. Since last year things have gotten worse. I can’t even explain it but there was a lot of being in court with my biological father. And I even got kicked out a couple of times. I wasn’t homeless but I was living a bit of everywhere. I went to my grandparents, aunts and best friends house. But last weekend it took a quick turn. On Sunday March 26th things got really down hill. My mother was going insane and I didn’t know how to react or how to feel. I have already experienced traumatic situations before with her but this one was different.It got so bad I called my brother and aunt both people I deeply trust. The cops eventually arrived bc the neighbors called the cops so my brother took me to his car and told me to wait inside. I saw cops put handcuffs on my mom and started walking with her the a police car. I started to have a panic attack and I started punching everything as they took my mother away. I didn’t know what was happening, I didn’t know if I was gonna see her again or if she was getting arrested. My brother and aunt came to the car and told me they were taking her to a hospital to see if she needs help. 3 days later they found drugs in her system that looked like she’s been doing drugs for 4 years and it could’ve killed her. I felt more guilt go onto my back. And I started blaming myself thinking I should’ve noticed and if I did it wouldn’t have got this bad. Along with that she got diagnosed with bipolar disorder. The low lows follows by her depression and anger which causes manic episodes. Only thing is that there’s no happiness in her disorder. Which explains a lot. She’s at a mental hospital right now, and me? I’m living with my grandparents. I don’t know what to do anymore or what I’m supposed to feel. I feel numb and hopeless. Maybe one of you can understand.